1. Field of The Invention
The present invention relates to solar cells. In particular, the invention relates to methods and apparatuses for efficient packaging of solar cells for space applications.
2. Description of The Related Art
Photovoltaic cells, commonly called solar cells, are well-known devices which convert solar energy into electrical energy. Solar cells have long been used to generate electrical power in both terrestrial and space applications. Solar cells offer several advantages over more conventional power sources. For example, solar cells offer a clean method for generating electricity. Furthermore, solar cells do not have to be replenished with fossil fuels. Instead, solar cells are powered by the virtually limitless energy of the sun. However, the use of solar cells has been limited because solar cells are a relatively expensive method of generating electricity. Nonetheless, the solar cell is an attractive device for generating energy in space, where low-cost conventional power sources are unavailable.
Typically, solar cells manufactured for space use have been of fairly small dimensions. Commonly, solar cells have had dimensions of 4 cm.times.6 cm or less. In space applications, hundreds or thousands of the small solar cells are interconnected together to form large solar arrays. In a typical manufacturing process, a solar cell manufacturer delivers hundreds or thousands of separate, unconnected, solar cells to a solar array assembler. Often, the solar cell manufacturer mounts a coverglass over each cell to protect the cells against space radiation and other environmental conditions. Alternatively, the solar cell manufacturer may ship bare cells to the array assembler. The array assembler then must provide the coverglass. The array assembler also interconnects the individual cells into large, suitably sized panels.
The use of individual coverglasses for each cell has several disadvantages. For example, it is expensive and time consuming to mount a separate coverglass on each cell. In addition, the use of small cells incurs several disadvantages. For example, the smaller the cell size, the more cells are required to form an array of a given size. The more cells which must be assembled, the greater the manufacturing costs. In addition, each cell must be tested individually before being assembled into a larger array. Thus, the greater the number of cells required, the greater the number of tests which must be performed. Furthermore, the smaller the cells, the greater the total cell edge length (i.e. the length of all cell sides summed together) for a given array size. Cell edges are typically prone to damage. Thus, the greater the total edge length, the more likely that at least some cells will be damaged during the manufacturing, transport, and assembly of the cells.